Casting machine



' Dec. 30, 1969 YOSHIJI mouE CASTING MACHINE s Sheets-Sheet 1 Filed Oct.5, 1966 INVENTOR- YOSH/J/ INOUE iaw ATTY'S YVOSHIJI INO'UE CASTINGMACHINE Dec. 30, 1969 6 Sheets-Sheet 2 Filed vOct. 8, 1966 mvE/v TORYOSHIJI INOUE I 'ATTY'S Dec. 30, 1969 YOSHIJHNQ'I'UE CASTING MACHINE" 6Sheets-Sheet 5 Filed Oct. 5. 1966 INVENTOR YOSH/J/ INOUE 5 M 1m fi iwwATTY'S Dec. 30, 1969 wast-IL" mdua 3,486,551

- CASTING 'iaAcumE Filed Oct. 5. 1966 e Sheets-Sheet 4 INVENTOR 'YOSH/Jluvou .21 4.) j/W Q M ATTY'S Dec. 30, 1969 YOSHIJI INOUE 3, 55

- I CASTING MACHINE Filed Oct. 5. 1966 e Sheets-Sheet 5 ATTY'S Dec. 30,1969 YOSHIJI 'INOUE 3,486,551

, CASTING MACHINE Filed Oct. 5, 1966 6 Sheets-Sheet 6 I\- a E Q P- gINVENTORY gOSH/Jl INOUE M W ATTY'S United States Patent 3,486,551CASTING MACHINE Yoshiji Inoue, Kobe, Japan, assignor to Kanzakl KokyuKoki Mfg. Co., Ltd.

Filed Oct. 3, 1966, Ser. No. 583,786 Claims priority, application Japan,July 9, 1966, 41/ 44,897 Int. Cl. B22d 13/00 US. Cl. 164-286 8 ClaimsABSTRACT OF THE DISCLOSURE The present invention relates to a method andapparatus for centrifugal casting and more especially to the method andapparatus for centrifugal casting having plural number of moulds,enabling the hole mechanisms automatically down extremely easy and, atthe same time, the casting continuously down.

In conventional centrifugal casting apparatus castings are repeatedlymade in one rotating mould and the successive steps of casting, cooling,de-moulding, scavenging, coating, and temperature re-adjusting of themould take a long time for the production of a casting, which makes theprocess ineflicient.

The present invention has for its object to overcome this disadvantage.

According to the present invention there is provided a method ofcentrifugally casting a plurality of workpieces comprising the steps ofmoving a set of centrifugal casting moulds cyclically in sequencethrough a number of working stations including a casting station inwhich a mould is rotated and receives a charge of molten metal, acasting removal station in which the mould is not rotated and thecasting is removed and at least one mould conditioning station forpreparing the mould for receiving a further charge of metal in thecasting station.

Further, according to the present invention there is providedcentrifugal casting apparatus comprising a mould-carrying turret mountedfor rotation about its axis, a set of centrifugal casting mouldsrotatably mounted in the turret at equal angular spacings and at thesame distance from the turret axis, disengageable driving means forselectively rotating each of the moulds, means for periodically rotatingthe turret in one direction through a predetermined angle so as to movethe moulds cyclically in sequence through a set of working stationsincluding a casting station provided with means for pouring a charge ofmolten metal into a rotating mould, a casting removal station providedwith means for disengaging the drive to the mould and for removing thecasting from the mould and at least one mould conditioning station forpreparing the mould for receiving a further charge of metal at thecasting station.

The dispersed positions of the castings, cooling, demoulding andconditioning stations such as for scavenging, coating and temperaturereadjusting enable each operation to be performed efficiently.

It will be noted that only one mechanism for carrying out each workingoperation is required and this serves several moulds.

ICC

Consequently the apparatus is simplified.

An embodiment of the invention will now be described by Way of examplewith reference to the accompanying drawings, in which- FIGURE 1 shows ageneral perspective view of the apparatus with parts broken away,

FIGURE 2 is a perspective view of a portion not shown in FIGURE 1,

FIGURE 3 shows in longitudinal section one mould and its drivingmechanism,

FIGURE 4 is a vertical section of the casting mechanism, 1

FIGURE 5 represents a Vertical longitudinal section through thede-moulding mechanism,

FIGURE 6 shows a vertical longitudinal section through the scavengingmechanism and FIGURE 7 is a vertical longitudinal section through thecoating mechanism.

The embodiment of the invention shown in the drawis a centrifugalcasting machine having six moulds 30 equally angularly spaced at 60intervals around the axis of a turret formed by a drum 21. The drum 21is rotatable about its axis and the moulds 30 are moved intermittentlythrough 60 steps by means of a driving mechanism to be described belowso that each mould 30 moves cyclically through six working stations A,B, C, D, E, F, in one complete revolution of the drum 21.

A working operation is carried out at each working station. Theoperations are: casting, cooling, de-moulding, scavenging, coating andtemperature readjusting.

An electric motor 11 drive a main shaft 52 by means of a reduction gear12, a pulley 51, a belt 13 and a pulley 14 on the main shaft 52. Themain shaft 52 carries a sun gear 15 which meshes with'six pinions 17.Power from the main shaft 52 is thus transmitted to the six pinions 17which are each rotatably mounted a free-moving clutch shaft 16. Thepinions 17 rotate continuously.

Each clutch shaft 16 carries a side clutch 18 which, when engaged,transmits the rotation of the associated pinion 17 to the clutch shaft16 so that a pinion 19 fixed to the clutch shaft 16 rotates through theclutch 18. The pinion 19 meshes with a mould-driving gear 20 whoserotation is transmitted to the mould 30 through a mouldmounting frame53. Accordingly, the six moulds 30 are selectively driven rotationallyby engagement of the six side clutches 18 effected by a cam to bedescribed below, so that in the working stations A, B, D, E, F, themoulds 30 rotate while the mould 30 in the working station C does notrotate. The term rotation used herein means a rotation around astationary axis and therefore it is distinctively used as a revolvingcircular movement.

The main shaft 52 is supported by the frame 22 which also carries thecam 23. Six cam-follower rollers 24 each rotatably mounted on a rollerfitted bed 70 engage cam 23. The surface of the cam 23 is not even andthus the push rod 25 moves back and forward in accordance with the saidmovement of the roller 24. By this movement of the push rod 25 the saiddog clutch 18 which relates with the push rod 25 moves back and forwardso as to engage or disengage the clutches 18 to start or stop therotation of the moulds 30.

In order to rotate the drum 21 intermittently, a ratchet wheel 27coaxial with the drum is fixed to it, a pawl carrier 54 is mounted forrocking movement about the drum axis on the ratchet wheel 27, and apressure-oil operated ram 26 has a piston rod 55 connected to the pawlcarrier 54. The pawl carrier 54 carries a driving pawl 28. The ratchetwheel 27 is also engaged by an anti-reversing pawl (not shown). To keepthe rotation of the drum 21 exactly at 60 degrees, the drum has sixrecessed locating bosses 29 spaced at 60 intervals and these recessedbosses are engaged by plungers 48 operated by locating cylinder 56.

Each mould-mounting frame 53 supports a back c ver 33 for the mould 30and the said back cover 33 has a push rod 32 for ejecting the castproduct 31 (FIG- URES 1 and 3). The push rod 32 is actuated by thepiston 49 of a pneumatic ram 40 mounted on the frame 22.

At the working station A (FIGURES 1 and 4) is located a castingmechanism having a front cover 34, a molten metal weighing vessel 35, areceptacle 37 for molten metal 36 and a channel 38 for molten metal 36.

At the working station B is located a cooling mechanism having waterspray piping 39 for cooling the mould in the working station B.

At the working station C (FIGURES 1 and 5) is located the demouldingmechanism comprising, as described above, the ram operated push rod 32and a shoot 41 on to which the casting 31 is pushed.

At the working station D (FIGURES 1 and 6) is a scavenging mechanismcomprising a carriage 42 mounted on rails 57, a rotary wire brush 43carried by the carriage 42 and arranged to rotate against the inner wallof the mould 30 and a vacuum suction system 44.

At the working station E (FIGURE 7) is a coating mechanism, a carriage47 mounted on rails 58, a compressed air nozzle 46, a spray nozzle 45for coating liquid and a tank 50 containing the coating liquid. At themould working position F is a temperature readjusting mechanism having awater spray piping system (not shown in the drawings) for temperaturereadjustment.

In operation, after the electric motor 11 and other power supplies havebeen switched on, the piston rod '55 of the ram 26 starts reciprocatingperiodically under the action of an oil pressure control mechanism (notshown in the drawings). This periodic reciprocating motion of the pistonrod 55 moves the ratchet wheel 27 periodically through steps of 60 inthe left direction only (anti-clockwise direction in FIGURE 1) so thatthe drum 21, being attached to the ratchet wheel 27 moves with it andeach mould 30 while making a stop at each of the working stations A, B,C, D, E and F in turn, revolves intermittently. Between such moves, therecessed locating bosses 29 on the said drum 21 are engaged by thelocating plungers 48 to position the drums correctly.

Power from the electric motor 11 is transmitted to the six pinions 17through the gearbox 12, pulley 51, belt 13, pulley 14, main shaft 52 andsun gear 15 so that the pinions 17 rotate continuously. The push rods 25move under the actions of the cam-follower rollers 24 as they travelround the cam track 23 on the frame 22 and as a result of this motion,each clutch periodically engages so as to drive its associated pinion19. The rotation of the pinion 19 is transmitted to the mould 30 throughthe mould driving gear 20 and the mouldmounting frame 53 so that themould 30 rotates. When however the clutch 18 is disengaged, the mould 30does not rotate.

The various working operations carried out at the respective workingstations A, B, C, D, E and F will now be described.

The Working station A, as shown in FIGURE 4 comprises a pouringmechanism for pouring molten metal 36 into the mould 30. When the mould30 is moved with the drum 21 60 by the ram 26 from position F toposition A and held there, the said pouring mechanism is advancedtowards the mould 30 by a hydraulic ram and the front cover 34 comesinto contact with the mould 30. As the mould 30 is rotationally drivenby the moulddriving gear 20 at this moment, the front cover 34 rotatesin contact with the mould 30. Then the molten metal weighing ladle 35tips forward to pour the molten metal 36 in the ladle 35 into the mould30 through the channel 38 in the receptacle 37. When the castingoperation has been finished and the molten metal is more or lesssolidified, the pouring mechanism is retracted to its original position.

Thereafter the drum 21 again turns through 60 to move the mould 30 tothe working station B from position A. Here cooling water from the waterspray pipe 39 cools down the mould 30 which rotates with the casting 31inside it, and about its stationary axis.

When the drum 21 again turns through 60, the mould 30 moves from theworking station B to station C and stays there and, at the same time,its rotation about its axis stops. The casting 31 is then removed fromthe mould 30 by the push rod 32 actuated by the plunger 49 operated bythe air cylinder 40, the back cover 33 pushing the casting 31 out ontothe shoot 41. At this moment, compressed air is blown into the clearance62 between the push rod 32 and the mould-mounting frame 53 and also theinside of the mould 30 through fluid passage 59, 60 and nozzles 61 inthe push rod 32, any residues of coating agents remaining on the pushrod 32, the inner wall of the mould-mounting frame 53 and the mould 30are readily removed but also the coating agents, which would otherwisebe likely to find their way into the clearance 62 leading onto the mould30, are readily prevented from entering. When the removal of the castproduct has been completed the push piston 49 is returned to itsoriginal position by the air cylinder 40.

Then the drum 21 again turns through 60 to move the mould 30 from theposition C to the station D, the clutch 18 being at the same timere-engaged to rotate the mould 30 again.

At the working station D, as shown in FIGURE 6, the scavenging mechanismmoves forward and the rotating wire brush 43 is inserted into the mould30 while pushing back the rod 32 which was left in the mould 30 in theprevious working step. As a result of the rotation of the wire brush 43,coating materials presenting on the inner wall of the mould 30 aredislodged and removed by the vacuum suction device 44. At the suctionport 64 of the suction pipe 63 of the vacuum suction device 44 is aflange-like passage control body 65 having a slightly smaller diameterthan the inner diameter of the mould 30 so that the air-flow speeds aregreatly accelerated at around the outer circumference and any particlesadhering to the inner wall of the mould 30 come under the powerfulinfluence of the suction force due to the centrifugal force of therotation of mould 30 and the particles are completely removed throughthe suction pipe 63.

When the scavenging operation finishes, the drum 21 again turns 60 andthe mould 30 leaving the working station D moves to the working stationE and stays there. At the working station E, as illustrated in FIGURE 7,is a coating mechanism, of which, when the mould 30 stops at the stationE, the carrier 47 moves forward to wards the mould 30 to hold the spraynozzle 45 in position for coating and the high-pressure air nozzle 46 inthe mould 30 so that the coating operation is effected by spraying themixture of coating material and air on to the inner wall of the mould 30which is rotating.

When the cooling operation is finished, the drum 21 again turns through60, and the mould 30 thus moves from the station E to the station F andstays there. At the working station F temperature readjustment iseffected by spraying temperature-readjustment water (generally coolingwater but pre-heating water) onto the mould as in the same manner asworking station B.

Then the drum 21 again turns through 60". When the mould 30 moves to aposition A from position F a complete operation starting from position Ato position F has been completed and this operation is now repeated.

The order of the working step has been given above in detail for onemould 30; all six moulds 30 undergo the same cycle of steps at intervalsof 60.

What I claim is:

1. Centrifugal casting apparatus comprising a mouldcarrying turretmounted for rotation about its axis, a set of centrifugal casting mouldsrotatably mounted in the turret at equal angular spacings and at thesame distance from the turret axis, disengageable driving means fdrselectively rotating each of the moulds, means for periodically rotatingthe turret in one direction through a predetermined angle so as to movethe moulds cyclically in sequence through a set of working stationsincluding a casting station provided with means for pouring a charge ofmolten metal into a rotating mould, a casting removal station providedwith means for disengaging the drive to the mould and for removing thecasting from the mould while stationary and at least one mouldeonditioning station for preparing the mould while rotating forreceiving a further charge of metal at the casting station.

2. Centrifugal casting apparatus according to claim 1, wherein thenumber of centrifugal casting moulds in the turret is equal to thenumber of working stations.

3. Centrifugal casting apparatus according to claim 1, wherein there area plurality of mould conditioning stations including a scavengingstation with means for removing residues from the internal wall surfacesof the mould and a coating station with means for applying a coating tothe internal wall surfaces of the mould.

4. Centrifugal casting apparatus according to claim 3, wherein eachmould includes an axially movable push rod for ejecting the casting atthe casting removal station and the scavenging station includes meansfor blowing compressed air along the push rod into the mould, means fordislodging residues from the inner wall surfaces of the mould andsuction means for removing the material so dislodged.

5. Centrifugal casting apparatus according to claim 1, wherein thepouring mechanism at the casting station in eludes a measuring ladlearranged to tip and discharge its contents into the mould when thequantity of molten metal in the measuring ladle reaches a predeterminedvalue corresponding to the required charge to be poured into the mould.

6. Centrifugal casting apparatus according to claim 1, wherein the meansfor selectively rotating each of the moulds comprises a motor-driven sungear co-axial with the turret, a pinion for each mould meshing with thesun gear and a clutch for each mould interposed between the pinion andthe mould, the said clutches being engageable or disengageableselectively by means of cam followers co-operating with a cam trackextending around the axis of the turret.

7. Centrifugal casting apparatus according to claim 1, wherein there area plurality of mould conditioning stations with the selectively operablemeans rotating a mould at each conditioning station.

8. Centrifugal casting apparatus according to claim 1, wherein the meansfor selectively rotating each of the moulds comprises a driven pinionfor each mould and a clutch for each mould interposed between the pinionand the mould, the said clutches being selectively engageable ordisengageable to rotate a corresponding mould or allow the same toremain stationary.

References Cited UNITED STATES PATENTS I. SPENCER OVERHOLSER, PrimaryExaminer D. W. JONES, Assistant Examiner US. Cl. X.R.

